VersaTune User Forum

I am wondering if someone could help me understand the radiator fan control settings. I see a primary and secondary trigger in the ECU definitions, but there are five on/off relay coolant temp points as well. What would control the fan speed?

Thanks

You need to adjust the relay temperature triggers. You can look up the ECT sensor volts vs coolant temperature in ECT Sensor calibration table.
See this picture for details on what each relay controls:

Thank you!

I was able to set the fan temp triggers to primary 186F (85C), and secondary to 193F (193F or roughly 90C). Basically, I just added 0.17 volts to the on/off fan relay triggers 1-4. I did not change fan relay trigger 5. Plan to reevaluate this during the colder season, if there is one in Texas.

Thanks for posting your steps. I modified the fan triggers last night with the identical 0.17 volt adjustment. Today in 33° C rush hour traffic with the air conditioning on the hugest temperature I saw was 203° F on the gauge.

I'm glad this was useful to you. In my climate radiator coolant temps were always a concern and I think this will keep the engine temp under control safer in the long run.

Tedley wrote: ↑July 28th, 2022, 1:17 pm Thanks for posting your steps. I modified the fan triggers last night with the identical 0.17 volt adjustment. Today in 33° C rush hour traffic with the air conditioning on the hugest temperature I saw was 203° F on the gauge.

That's very good to know that your problem is resolved!